Certain chromosomal regions called common fragile sites are prone to difficulty during replication. Many tumors have been shown to contain alterations at fragile sites. Several models have been proposed to explain why these sites are unstable. Here we describe work to investigate models of fragile site instability using a yeast artificial chromosome carrying human DNA from a common fragile site...

Fragile X syndrome is now a well established common clinical entity and most of those who are aware of the condition probably know that it takes its name from a rare fragile site (FRAXA) on the X chromosome. This is the best known fragile site and its clinical significance is clear. Similar, but a little less known is FRAXE, a fragile site close to that associated with fragile X syndrome, but i...

The present study explored the behavioral profile of individuals with fragile X syndrome during adolescence and adulthood. Individuals with both fragile X syndrome and autism (n  =  30) were compared with (a) individuals diagnosed with fragile X syndrome (but not autism; n  =  106) and (b) individuals diagnosed with autism (but not fragile X syndrome; n  =  135) on measures of autism symptoms, ...

The objective of this text is to develop the theory of social health insurance (SHI; the expression used especially in the United States is “public health insurance,” which will be viewed as one variant of SHI here). While a good deal is known about the demand and supply of private insurance, the theoretical basis of SHI is much more fragile. Specifically, on the demand side, what are the reaso...

Human chromosomal fragile sites are specific genomic regions which exhibit gaps or breaks on metaphase chromosomes following conditions of partial replication stress. Fragile sites often coincide with genes that are frequently rearranged or deleted in human cancers, with over half of cancer-specific translocations containing breakpoints within fragile sites. But until recently, little direct ev...

We report the genetic localisation of the fragile site at Xq27.3 associated with fragile X syndrome. The position of the fragile site within the multipoint linkage map was determined using two polymorphic microsatellite AC repeat markers FRAXAC1 and FRAXAC2. These markers were physically located within 10 kilobases and on either side of the p(CCG)n repeat responsible for the fragile site. FRAXA...